At some point, I think that Marten needs to sit down with Pintsize and talk about his impulse control issues. From his expression in panel 2, I'm also thinking that being nearly stomped into a flat metal plate wasn't a possible outcome that he'd foreseen. All joking aside, he's really putting himself in serious danger at this point, and for what? A few passing moments of anarchic joy? How many times has Marigold had to reboot him because of damage he's sustained now?
So, how did Fairy Girl know where to bring Pintisize? I've got a feeling that Marten has soldered a plate to Pintsize that says something like: "If found, please return Pintsize to Apartment 22, 141 Dwight Street, Northamton, MA and I apologise in advance for whatever he did."
Seriously, they need to find him a hobby that stops him from getting bored like this or he'll end up killing himself at some point!